TORONTO (AP) — Canada is getting a fourth vaccine to prevent COVID-19 as the country's health regulator has cleared a Johnson & Johnson shot that works with just one dose instead of two, officials said Friday.

Health experts are eager for a one-and-done option to help speed vaccination. Canada has also approved vaccines from Pfizer, Moderna and AstraZeneca and Health Canada is the first major regulator to approve four different vaccines, said Dr. Supriya Sharma, Health Canada’s chief medical adviser.

Like many countries, Canada does not have domestic production and has struggled with an immediate shortage of vaccines. The U.S. so far isn’t allowing locally made vaccines to be exported, so Canada — like the other U.S. neighbor, Mexico — has been forced to get vaccines from Europe and Asia.

Prime Minister Justin Trudeau said Canada has an agreement with Johnson & Johnson for 10 million doses before September. It was not immediately clear when Canada would get its first shipments of those.

But Trudeau announced Pfizer would deliver an additional 1.5 million doses to Canada in March and another 1 million doses ahead of schedule in both April and May.

“We have reasons to be optimistic. We’re going to be able to move things forward,” Trudeau said. “But at the same time, we also know that these are global supply chains that are being set up and there’s always possibility for disruptions.”

The U.S. approved Johnson and Johnson last month. The U.S. Food and Drug Administration said J&J’s vaccine offers strong protection against what matters most: serious illness, hospitalizations and death. One dose was 85% protective against the most severe COVID-19 illness in a massive study that spanned three continents — protection that remained strong even in countries such as South Africa, where the variants of most concern are spreading.

J&J also is seeking authorization for emergency use of its vaccine in Europe and from the World Health Organization. The company aims to produce about 1 billion doses globally by the end of the year. Last month, the island nation of Bahrain became the first to clear its use.

The vaccine shortage is so acute in Canada that provincial governments are now saying they will extend the interval between the two doses of Pfizer, Moderna and AstraZeneca vaccines to four months rather than three to four weeks so they can quickly inoculate more people.

“It is a reasonable recommendation. If we can get earlier doses, we don't have to wait for four months to give second doses if the supply opens up,” Sharma said.

Retired Gen. Randy Hillier, who leads the vaccine program Canada's most populous province of Ontario, expects to get everyone eligible in the province a first shot by June 20. The Manitoba provincial government is now predicting it will be able to offer all eligible adults the first dose this spring — months ahead of its previous plan.

“It is possible that we have further good news and good predictions to share in the coming weeks," Trudeau said.

Trudeau said officials have been assured by the European Union that Pfizer and Moderna vaccines deliveries to Canada won't be disrupted. A shipment of over a quarter million AstraZeneca vaccines destined for Australia has been blocked from leaving the European Union in the first use of a European export control system to make sure big pharma companies respect their local contracts.

Trudeau noted that Canada is getting Pfizer and Moderna doses from Europe now and said those two companies are not likely to face export disruptions from Europe. He said Canada won't get AstraZeneca vaccines doses from Europe for months. Canada received 500,000 AstraZeneca doses from India this month.

The provincial Ontario government, meanwhile, said it is lifting its stay-at-home order next week in Toronto, Canada's largest city. Ontario will allow retailers to reopen for in-person shopping, but only with a 25% capacity limit. Many restrictions will remain in place. Indoor and outdoor diving service will continue to be prohibited. Hair salons also can't reopen.

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